U.S. patent number 4,692,924 [Application Number 06/783,967] was granted by the patent office on 1987-09-08 for laser treatment apparatus.
This patent grant is currently assigned to Tokyo Kagaku Kakai Kabushiki Kaisha. Invention is credited to Masatsugu Kijima, Hiroshi Koizumi, Sinya Tanaka.
United States Patent |
4,692,924 |
Koizumi , et al. |
September 8, 1987 |
**Please see images for:
( Certificate of Correction ) ** |
Laser treatment apparatus
Abstract
A laser treatment apparatus for determining that the output
power of a treatment laser beam is proper in accordance with the
selected output power. The treatment apparatus comprises a laser
source for generating a treatment laser pulse beam, a laser optical
path for guiding the treatment laser pulse beam toward an object to
be treated, a power setting means for controlling the laser source
to set the power output of the treatment laser pulse beam, and a
radiation switch for selectively switching the laser source on and
off. A safety device is provided to cause the laser source to
output a checking laser pulse beam prior to actual transmission of
the treatment laser pulse beam and at a time after the activation
of the radiation switch. The checking laser pulse beam has a power
corresponding to the actual power of the treatment laser pulse beam
to be outputted by the laser source. A power detector detects the
power output of the checking laser pulse beam and a comparator
determines whether the power output of the checking laser pulse
beam is correct in view of the power of the treatment laser pulse
beam set by the power setting means.
Inventors: |
Koizumi; Hiroshi (Saitama,
JP), Kijima; Masatsugu (Tokyo, JP), Tanaka;
Sinya (Tokyo, JP) |
Assignee: |
Tokyo Kagaku Kakai Kabushiki
Kaisha (Tokyo, JP)
|
Family
ID: |
15502932 |
Appl.
No.: |
06/783,967 |
Filed: |
October 4, 1985 |
Foreign Application Priority Data
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Oct 6, 1984 [JP] |
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59-150720[U] |
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Current U.S.
Class: |
372/30;
372/38.03; 372/38.09; 606/11; 606/12; 607/89 |
Current CPC
Class: |
H01S
3/131 (20130101) |
Current International
Class: |
H01S
3/131 (20060101); H01S 003/13 () |
Field of
Search: |
;372/25,30,38 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wan; Gene
Attorney, Agent or Firm: Finnegan, Henderson Farabow,
Garrett Dunner
Claims
What is claimed is:
1. A laser treatment apparatus comprising:
a laser source for generating a treatment pulse beam;
a laser optical path for guiding said treatment laser pulse beam
toward an object to be treated thereby;
a power setting means for controlling said laser source to set the
power output of said treatment laser pulse beam;
a radiation switch for selectively switching said laser source to
output said treatment laser pulse beam or to stop the output of
said treatment laser pulse beam;
a safety device for enabling said laser source to output a checking
laser pulse beam prior to the transmission of said treatment laser
pulse beam through said laser optical path and after the activation
of said radiation switch to select the output of said treatment
laser pulse beam, said checking laser pulse beam having a power
corresponding to the actual power of said treatment laser pulse
beam outputted by said laser source;
a power detector for detecting the power output of said checking
laser pulse beam outputted from said laser source; and
a comparator for comparing said detected power output of said
checking laser pulse beam with a predetermined power level
corresponding to the power of a treatment laser pulse beam as set
by said power setting means, said safety device for preventing the
transmission of said treatment laser beam from said laser source if
said comparator determrines that said power of said checking laser
pulse does not correspond to said predetermined power level
corresponding to a treatment laser pulse beam as set by said power
setting means.
2. A laser treatment apparatus according to claim 1, further
comprising an abnormality warning indicator for indicating an
abnormality when said power output of said checking laser pulse
beam does not correspond to said predetermined power level of a
treatment laser pulse beam as set by said power setting means.
3. A laser treatment apparatus according to claim 1, wherein said
apparatus further comprises a shutter disposed in said optical
laser path for preventing said checking laser pulse beam and said
treatment laser pulse beam from being transmitted to said object to
be treated, said safety device including means for closing said
shutter when said checking laser pulse beam is outputted from said
laser source and for opening said shutter when said comparator
determines that said power output of said checking laser pulse beam
corresponds to said predetermined power level corresponding to a
treatment laser pulse beam as set by a power setting means.
4. A laser treatment apparatus according to claim 3, wherein said
apparatus further comprises a shutter opening and shutting
detection means for detecting whether said shutter is open or shut,
said safety device further including means for preventing said
laser source from outputting said checking laser pulse beam and
said treatment laser pulse beam responsive to said shutter opening
and shutter detection means detecting that said shutter is in said
open state prior to said checking laser pulse beam being
outputted.
5. A laser treatment apparatus according to claim 1, wherein said
power detector includes means for photoelectrically detecting the
power level of said checking laser pulse beam.
6. A laser treatment apparatus according to claim 1, wherein said
safety device includes means for enabling the transmission of said
treatment laser pulse beam along said laser optical path only in
response to the activation of said radiation switch after said
comparator determines that the power output of said checking laser
pulse beams corresponds to said predetermined power level of a
treatment laser pulse beam as set by said power setting means.
7. A laser treatment apparatus according to claim 6, wherein said
safety device includes means for enabling said laser source to
output a different laser pulse beam in response to the activation
of said radiation switch after the selection of a different power
output for said laser pulse beam by said power setting means, said
different checking laser pulse beam having a power level
corresponding to the actual power level of said different treatment
laser pulse beam.
8. A laser treatment apparatus comprising:
a laser source for generating a treatment laser pulse beam;
a laser optical path for guiding said treatment laser pulse beam to
an object to be treated thereby;
a power setting means for setting the power of said treatment laser
pulse beam generated by said laser source;
a radiation switch for selectively switching said laser source to
output said treatment pulse beam or to inhibit the output of said
treatment laser pulse beam, said laser power source for outputting
a checking laser pulse beam having a power corresponding to the
actual power of said treatment laser pulse beam;
a power detector for detecting said power of said checking laser
pulse beam; and
a power indicator for indicating said power of said checking laser
pulse beam as detected by said power detector.
9. A laser treatment apparatus according to claim 8, wherein said
apparatus further comprises:
a comparator for comparing said power of said checking laser pulse
beam with a predetermined power level of a treatment laser pulse
beam having a power corresponding to said power output set by said
power setting means; and
a safety device for inhibiting the transmission of said treatment
laser pulse beam along said laser optical path responsive to said
comparator detecting that said power of said checking laser pulse
beam does not correspond with the power of a treatment laser pulse
beam corresponding to the power output set by said power setting
means.
10. A laser treatment apparatus according to claim 9, further
comprising an abnormality warning means for indicating an
abnormality responsive to said comparator detecting that said power
output of said checking laser pulse beam does not correspond with a
power of a treatment laser pulse beam having said power output set
by said power setting means.
11. A laser treatment apparatus according to claim 9, further
comprising a shutter disposed in said laser optical path for
preventing said checking laser pulse beam and said treatment laser
pulse beam from being transmitted along said laser optical path,
said safety device including means for shutting said shutter
responsive to said checking laser beam being outputted from said
laser power source and for opening said in response to said
comparator detecting that the power of said checking laser pulse
beam corresponds to the power of a treatment laser pulse beam
having said power output set by said power setting means.
12. A laser treatment apparatus according to claim 11, further
comprising a shutter opening and shutting detection means for
detecting whether said shutter is open or closed, said safety
device including means for preventing said laser source from
outputting said checking laser pulse beam and said treatment laser
pulse beam responsive to said shutter opening and shutting
detection means detecting that said shutter is open at a time
preceding the output of said checking laser pulse beam by said
laser power source.
13. A laser treatment apparatus according to claim 8, wherein said
power detector includes means for photoelectrically detecting the
power of said checking laser pulse beams.
14. A laser treatment apparatus according to claim 8, wherein said
power detector includes means for detecting the power of said
treatment laser pulse beam and said power indicator includes means
for indicating said detected power of said treatment laser pulse
beam.
15. A laser treatment apparatus according to claim 9, wherein said
safety device includes means for enabling said laser source to
generate said treatment laser pulse beam in response to the
activation of said radiation switch only after said comparator
detects that the power of said checking laser pulse beam
corresponds to a treatment laser pulse beam having said power
output set by said power setting means.
16. A laser treatment apparatus according to claim 8, wherein in
response to said power setting means setting said power output of
said treatment laser pulse beam to a different level, said laser
source generates a different checking laser pulse beam having a
power level corresponding to said different power output and
wherein said power detector detects said power of said different
checking laser pulse beam and said power indicator indicates said
detected power of said different checking laser beam.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a laser treatment apparatus.
2. Description of the Related Art
A conventional laser treatment apparatus generally includes power
setting means and a radiation switch. In this known art, an object
to be treated, e.g. a human, is radiated for its treatment with a
treatment laser pulse beam which is generated by turning the
radiation switch on. In this case, if such a treatment laser beam
should have a power output higher than a preset value, the object
to be treated would be damaged. Accordingly, in the conventional
apparatus, a check of the radiation output is carried out with a
shutter of a laser optical system shut in order to confirm whether
or not the power output of the treatment laser beam is in accord
with the preset power value every time before the treatment laser
beam is generated.
However, in the conventional laser treatment apparatus, the
confirmation of a correct power output value of the treatment laser
beam requires a checking radiation switch to be manually turned on
to generate a checking laser pulse beam before the radiation switch
is turned on. Accordingly, it requires much time and labor for such
confirmation, which often results in an obstacle for carrying out a
prompt treatment after confirming whether or not there exists
something abnormal in the power output.
The present invention is accomplished in order to eliminate the
above-mentioned inconvenience inherent in the conventional laser
treatment apparatus.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to
provide a laser treatment apparatus in which a confirmation of
whether or not there exists something abnormal in the output value
of a treament laser beam is promptly made available, so that
undivided attention can be concentrated on a treatment.
The features of the present invention reside in the point that a
laser treatment apparatus according to the invention includes a
safety device for outputting a laser pulse beam for checking
whether a treatment laser pulse beam is in accord with a preset
power output before the treatment laser pulse beam is generated by
turning a radiation switch on, and stopping the radiation of the
treatment laser pulse beam or indicating an existence of an
abnormality when the output of the checking laser pulse beam is
found to be abnormal compared with the preset power output.
The function of a laser treatment apparatus according to the
present invention is such that a checking laser pulse beam is
automatically outputted by a safety device before a treatment laser
pulse beam is outputted in treatment.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, novel features and advantages of the
present invention will become more apparent from the description on
exemplary embodiment of the invention when read in conjunction with
the accompanying drawings in which:
FIG. 1 is a block diagram showing a laser treatment apparatus
according to a first embodiment of the present invention;
FIG. 2 is a flow chart of the laser treatment apparatus of FIG. 1;
and
FIG. 3 is likewise a flow chart showing a laser treatment apparatus
according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Preferred embodiments of the present invention will be described
hereunder with reference to the accompanying drawings.
FIGS. 1 and 2 illustrate a laser treatment apparatus according to a
first embodiment of the present invention. In FIG. 1, reference
numeral 1 denotes a laser optical system, reference numeral 2
denotes a pulse laser apparatus, and l denotes a laser optical
axis. The laser optical system 1 is provided with a semitransparent
mirror 3 and a shutter 4. The shutter 4 is actuated by a shutter
actuator 5. The shutter 4 has the function for shielding a laser
pulse beam. The semitransparent mirror 3 has a 99% transmission and
the remaining 1% of the laser beam is reflected thereon and guided
to a light receiving element 7.
The pulse laser apparatus 2 is driven by a laser electric power
source 8. The on and off operation of the electric power source 8
is controlled by CPU 9 serving as a control center of the laser
treatment apparatus. The CPU 9 also serves as a primary portion of
the safety device. The CPU 9 is inputted with a radiation order
information from a radiation switch 10, a power setting information
from a power setting switch 11 serving as power setting means, a
shutter opening and shutting information from a shutter opening and
shutting detection circuit 12, and an output information from a
comparator 13. The radiation switch 10 outputs 2 pieces of
equalizing pulses as the radiation order information in succession.
A first equalizing pulse is adapted to use for outputting a
checking laser pulse beam. On the other hand, a second equalizing
pulse is adapted to use for outputting a treatment laser pulse
beam. The comparator 13 is adapted to detect whether or not there
is something abnormal in the output of the treatment laser pulse
beam. The comparator 13 constitutes an abnormality detecting
circuit together with the light receiving element 7, and a
converter 14. When the power setting switch 11 is manipulated,
standard level information corresponding to a power set through the
CPU 9 is inputted in the comparator 13. The comparator 13 compares
the standard level information with detecting information outputted
from the converter 14, and if something abnormal is found, outputs
abnormality warning information toward the CPU 9. The comparator 13
also has the function for outputting information to an abnormality
warning indication circuit 15.
The converter 14 has the function for converting the output of the
light receiving element 7 to the output of the laser pulse beam
based on the output of the light receiving element 7. The output of
the converter 14 is supplied to the comparator 13 as well as a
power indication circuit 16. The power indication circuit 16
indicates the radiated power of the laser pulse beam.
The shutter opening and shutting detection circuit 12 is inputted
with the output of the light receiving element 17. The light
receiving element 17 is adapted to receive radiation light emitted
from a light emitting element 18. The radiation light emitted from
the light emitting element 18 is shielded when the shutter 4 is
shut. When the shutter 4 is open, the radiation light reaches the
light receiving element 17 through an opening 4a. If the radiation
switch 10 is turned on when the shutter 4 is shut, the CPU 9 issues
an order to turn the laser electric power source 11 on for
radiating one shot of a checking laser pulse beam. The details of
the controlling thereof will be described next with reference to a
flow chart of FIG. 2.
At a time when treatment is started, the power switch 11 is
manipulated to set the power of the treatment laser pulse beam
(step 19). Next, the radiation switch 10 is turned on (step 20).
When the radiation switch 10 is turned on, a radiation switch-on
radiation order information is inputtted by the CPU 9. Then, the
CPU 9 carries out a process for checking whether or not the shutter
4 is closed (step 21). Before the treatment is started, the shutter
4 is normally shut. However, if the shutter 4 is not shut,
abnormality warning information is inputted to the abnormality
warning indication circuit 15 through the CPU 9 (step 22). When the
shutter 4 is shut, the CPU 9 outputs order information for
generating a checking laser pulse beam toward the laser electric
power source 8 (step 23). By this, the checking laser pulse beam is
radiated from the laser apparatus 2. A part of the checking laser
pulse beam is reflected on the semitransparent mirror 3, guided to
the light receiving element 7, and its photoelectric transfer
output is guided to the converter 14. The output of the converter
14 is inputted in the comparator 13, and the comparator 13 checks
whether or not the power of the checking laser pulse beam is in
accord with the preset power (step 24). When the power of the
checking laser pulse beam is not in accord with the preset power,
the comparator 13 outputs abnormality warning information, and the
abnormality warning indication circuit 15 indicates the improper
power level (step 22). At the same time, the abnormality warning
information is inputted in the CPU 9 to stop the generation of the
treatment laser pulse beam. When the abnormality warning
information is not inputted from the comparator 13, the CPU 9
outputs a driving order signal toward the shutter actuating circuit
5. When the shutter 4 is opened (step 25) due to the foregoing, a
shutter open signal is inputted by the CPU 9 from the shutter
opening and shutting detection circuit 12. Based on this shutter
open information, the CPU 9 outputs an order signal for generating
a treatment laser pulse beam toward the laser electric power source
8 (step 26). After the treatment laser pulse beam is generted, the
CPU 9 outputs a shutter actuating signal to the shutter driving
circuit 5. As a result, the shutter 4 is shut (step 27), and
generation of the treatment laser pulse beam is completed.
FIG. 3 illustrates the operation sequence of a laser treatment
apparatus according to a second embodiment of the present
invention. The power of the laser pulse beam is preset in the step
28. When the switch of the electric power source is turned on in
the step 29, there starts the checking whether the shutter 4 is
shut or not in the step 30. When the shutter is found to be open,
the abnormality is indicated in the abnormality indication warning
indication circuit 15 (step 31). When the shutter 4 is found to be
closed, the checking laser pulse beam is generated in the step 31'.
The power of the checking laser pulse beam is indicated in the
power indication circuit 16 (step 32). Next, a checking is carried
out whether or not the power of the checking laser pulse beam is in
accord with the preset power (step 33). When it is found to be "not
in accord", in other words, when an abnormality is found, the
abnormality warning indication is indicated in the step 31. When no
abnormality is found, a shutter actuation order is outputted from
the CPU 9 upon turning-on of the switch 10 of the radiation switch
10 in the step 34. As a result, the shutter 4 is opened (step 35).
Thereafter, order information for generating the treatment laser
pulse beam is outputted toward the laser electric power source 8
from the CPU 9. By this, a treatment laser pulse beam is generated
(step 36). A part of the treatment laser pulse beam is reflected on
the semitransparent mirror 3, received by the light receiving
element 7, and the photoelectric transfer signal is inputted in the
converter 14, and the power of the treatment laser pulse beam is
indicated in the indication circuit 16 (step 37). Thereafter, the
CPU 9 outputs the shutter closing order information toward the
shutter actuation circuit 5. As a result, the shutter 4 is closed
(step 38).
Thereafter, it is determined whether or not the preset power is
altered in the step 39. When the power of the treatment laser pulse
beam is altered by manipulating the power setting switch 11 after
the radiation switch 10 is turned on, the processes in the steps 31
and 33 are carried out in order to confirm whether an abnormality
exists in the treatment laser pulse beam. In the case the radiation
switch 10 is turned on without manipulating the power setting
switch 11, only the treatment laser pulse beam is outputted
everytime the radiation switch 10 is turned on assuming that there
exists no abnormality in the preset power.
Although in this second embodiment, the checking laser pulse beam
is preliminarily outputted before the radiation switch 10 is turned
on, the checking laser pulse beam may be outputted after the
radiation switch is turned on.
As described in the foregoing, a laser treatment apparatus
according to the invention includes a safety device for outputting
a laser pulse beam for checking whether a treatment laser pulse
beam is in accord with a preset power output before the treatment
laser pulse beam is generated by turning a radiation switch on, and
stopping the radiation of the treatment laser pulse beam or
indicating an existence of an abnormality when the output of the
checking laser pulse beam is found to be something abnormal
compared with the preset power output. Accordingly, a confirmation
of whether or not there exists an abnormality in the output value
of a treatment laser beam is promptly made available, so that
undivided attention can be concentrated on a treatment.
Although the present invention has been described in connection
with preferred embodiments thereof, it will be appreciated that
many modifications and variations will readily occur to those
skilled in the art without departing from the spirit and scope of
the invention.
* * * * *